Re: column * row ??

*To*: mathgroup at smc.vnet.net*Subject*: [mg28798] Re: [mg28791] column * row ??*From*: BobHanlon at aol.com*Date*: Sun, 13 May 2001 03:28:46 -0400 (EDT)*Sender*: owner-wri-mathgroup at wolfram.com

n = 5; colvec = Table[ToExpression["a"<>ToString[k]], {k, n}]; rowvec = Table[ToExpression["b"<>ToString[k]], {k, n}]; Outer[Times, colvec, rowvec] Bob Hanlon In a message dated 2001/5/12 9:50:46 PM, jrchaff at mcn.net writes: >Can someone tell me a way to mimic the building of >an N x N matrix by multiplying a column vector >on left times a row vector on right ? (both vectors >of length N) - I mean in Mathematica, of course. > >i.e, want the result, > >(colvec){a1,a2, .. aN} * (rowvec){b1,b2,..bN} = > >result is matrix: > >{{a1*b1 a1*b2 ..... a1*bN}, > {a2*b1 a2*b2 ..... a2*bN}, > ... ... ... , > {aN*b1 aN*b2 ..... aN*bN}} > > >When I try this in Mathematica all I can figure out >how to produce is the standard dot-product. If I >try the 'transposed' lists/matrices, I get an error, >even tho the product is defined by basic rules of >matrix multiplication. >